[PATCH v2] (powerpc/512) Fix possible `dma_unmap_single()` on uninitialized pointer

Subsystems: linux for powerpc (32-bit and 64-bit), linux for powerpc embedded mpc5xxx, the rest

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2 messages, 2 authors, 2025-06-10 · open the first message on its own page

[PATCH v2] (powerpc/512) Fix possible `dma_unmap_single()` on uninitialized pointer

From: Thomas Fourier <hidden>
Date: 2025-06-10 14:29:50

If the device configuration fails (if `dma_dev->device_config()`),
`sg_dma_address(&sg)` is not initialized and the jump to `err_dma_prep`
leads to calling `dma_unmap_single()` on `sg_dma_address(&sg)`.

Signed-off-by: Thomas Fourier <redacted>
---
 arch/powerpc/platforms/512x/mpc512x_lpbfifo.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
index 9668b052cd4b..f251e0f68262 100644
--- a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
+++ b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c

@@ -240,10 +240,8 @@ static int mpc512x_lpbfifo_kick(void)
 	dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 
 	/* Make DMA channel work with LPB FIFO data register */
-	if (dma_dev->device_config(lpbfifo.chan, &dma_conf)) {
-		ret = -EINVAL;
-		goto err_dma_prep;
-	}
+	if (dma_dev->device_config(lpbfifo.chan, &dma_conf))
+		return -EINVAL;
 
 	sg_init_table(&sg, 1);

-- 
2.43.0

Re: [PATCH v2] (powerpc/512) Fix possible `dma_unmap_single()` on uninitialized pointer

From: Christophe Leroy <hidden>
Date: 2025-06-10 16:50:35


Le 10/06/2025 à 16:29, Thomas Fourier a écrit :

[Vous ne recevez pas souvent de courriers de fourier.thomas@gmail.com. Découvrez pourquoi ceci est important à https://aka.ms/LearnAboutSenderIdentification ]

If the device configuration fails (if `dma_dev->device_config()`),
`sg_dma_address(&sg)` is not initialized and the jump to `err_dma_prep`
leads to calling `dma_unmap_single()` on `sg_dma_address(&sg)`.

Signed-off-by: Thomas Fourier <redacted>

Reviewed-by: Christophe Leroy <redacted>

quoted hunk

---
  arch/powerpc/platforms/512x/mpc512x_lpbfifo.c | 6 ++----
  1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
index 9668b052cd4b..f251e0f68262 100644
--- a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
+++ b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c

@@ -240,10 +240,8 @@ static int mpc512x_lpbfifo_kick(void)
         dma_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;

         /* Make DMA channel work with LPB FIFO data register */
-       if (dma_dev->device_config(lpbfifo.chan, &dma_conf)) {
-               ret = -EINVAL;
-               goto err_dma_prep;
-       }
+       if (dma_dev->device_config(lpbfifo.chan, &dma_conf))
+               return -EINVAL;

         sg_init_table(&sg, 1);

--

2.43.0

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